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author | Christoph Hellwig <hch@lst.de> | 2015-01-14 10:42:32 +0100 |
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committer | Jens Axboe <axboe@fb.com> | 2015-01-20 14:02:58 -0700 |
commit | b4caecd48005fbed3949dde6c1cb233142fd69e9 (patch) | |
tree | 1fdd9b7c15568c79eb3c1ed84a39858ddbcbc88b /security/security.c | |
parent | 97b713ba3ebaa6c8d84c2c720f5468a7c6a6eb4e (diff) | |
download | linux-stable-b4caecd48005fbed3949dde6c1cb233142fd69e9.tar.gz linux-stable-b4caecd48005fbed3949dde6c1cb233142fd69e9.tar.bz2 linux-stable-b4caecd48005fbed3949dde6c1cb233142fd69e9.zip |
fs: introduce f_op->mmap_capabilities for nommu mmap support
Since "BDI: Provide backing device capability information [try #3]" the
backing_dev_info structure also provides flags for the kind of mmap
operation available in a nommu environment, which is entirely unrelated
to it's original purpose.
Introduce a new nommu-only file operation to provide this information to
the nommu mmap code instead. Splitting this from the backing_dev_info
structure allows to remove lots of backing_dev_info instance that aren't
otherwise needed, and entirely gets rid of the concept of providing a
backing_dev_info for a character device. It also removes the need for
the mtd_inodefs filesystem.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'security/security.c')
-rw-r--r-- | security/security.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/security/security.c b/security/security.c index 18b35c63fc0c..a0442b20f001 100644 --- a/security/security.c +++ b/security/security.c @@ -726,16 +726,15 @@ static inline unsigned long mmap_prot(struct file *file, unsigned long prot) return prot | PROT_EXEC; /* * ditto if it's not on noexec mount, except that on !MMU we need - * BDI_CAP_EXEC_MMAP (== VM_MAYEXEC) in this case + * NOMMU_MAP_EXEC (== VM_MAYEXEC) in this case */ if (!(file->f_path.mnt->mnt_flags & MNT_NOEXEC)) { #ifndef CONFIG_MMU - unsigned long caps = 0; - struct address_space *mapping = file->f_mapping; - if (mapping && mapping->backing_dev_info) - caps = mapping->backing_dev_info->capabilities; - if (!(caps & BDI_CAP_EXEC_MAP)) - return prot; + if (file->f_op->mmap_capabilities) { + unsigned caps = file->f_op->mmap_capabilities(file); + if (!(caps & NOMMU_MAP_EXEC)) + return prot; + } #endif return prot | PROT_EXEC; } |